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NAME

       frexp,  frexpf,  frexpl  -  extract mantissa and exponent from a double
       precision number

SYNOPSIS

       #include <math.h>

       double frexp(double num, int *exp);
       float frexpf(float num, int *exp);
       long double frexpl(long double num, int *exp);

DESCRIPTION

       These  functions  shall  break  a  floating-point  number  num  into  a
       normalized  fraction  and  an integral power of 2. The integer exponent
       shall be stored in the int object pointed to by exp.

RETURN VALUE

       For finite arguments, these functions shall return the  value  x,  such
       that  x  has a magnitude in the interval [0.5,1) or 0, and num equals x
       times 2 raised to the power *exp.

       If num is NaN, a NaN shall be  returned,  and  the  value  of  *exp  is
       unspecified.

       If num is ±0, ±0 shall be returned, and the value of *exp shall be 0.

       If  num  is  ±Inf,  num  shall  be  returned,  and the value of *exp is
       unspecified.

ERRORS

       No errors are defined.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       isnan()  ,  ldexp()  ,  modf()  ,  the  Base  Definitions   volume   of
       IEEE Std 1003.1-2001, <math.h>

COPYRIGHT

       Portions  of  this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
       --  Portable  Operating  System  Interface (POSIX), The Open Group Base
       Specifications Issue 6, Copyright (C) 2001-2003  by  the  Institute  of
       Electrical  and  Electronics  Engineers, Inc and The Open Group. In the
       event of any discrepancy between this version and the original IEEE and
       The  Open Group Standard, the original IEEE and The Open Group Standard
       is the referee document. The original Standard can be  obtained  online
       at http://www.opengroup.org/unix/online.html .